Apparatus and methods for bone access and cavity preparation

Abstract

Apparatus and methods for preparing the interior of a bone for therapy. The therapy may include therapy for a bone fracture. The apparatus and methods may involve orienting a surgical instrument for proper deployment in the interior of the bone. An instrument guide may be positioned and retained against translation along, and rotation about one or more of three substantially orthogonal axes. Apparatus placed exterior to the bone may register the guide to a region inside the bone that is designated for preparation or treatment. One or more broaching members may be used to prepare the region for treatment. A broaching member may be expandable inside the bone. A broaching member may be flexible such that it broaches bone having a relatively lower density and it leaves bone having a relatively higher density substantially intact.

1 - 3 . (canceled) 
     
     
         35 . Apparatus for preparing a. bone cavity for implantation of an implant, the apparatus comprising:
 a drive shaft defining a radial direction and a longitudinal direction;   a plurality of broaching members, each broaching member having a proximal end and a distal end; and   a hub fixed to a terminal end of the drive shaft, the hub including a hub distal end and a plurality of faces extending away from the hub distal end toward a hub proximal end, the faces spaced circumferentially apart from each other about the longitudinal direction to define openings therebetween;   wherein:
 the hub supports each broaching member; 
 in operation, a distal end of each broaching member extends in the radial direction; and 
 each face follows a constant radius along the longitudinal direction. 
   
     
     
         36 . The apparatus of  claim 35  wherein each broaching member includes a cutting edge. 
     
     
         37 . The apparatus of  claim 35  further comprising, when the hub is a distal hub, a proximal hub fixed, proximal to the distal hub, to the drive shaft, wherein the proximal end of each broaching member is supported by the proximal hub. 
     
     
         38 . The apparatus of  claim 35  wherein the hub is constructed of laser-cut tube. 
     
     
         39 . The apparatus of  claim 35  wherein the hub distal end includes a flat, disc-shaped cap. 
     
     
         40 . The apparatus of  claim 39  wherein the cap borders the openings. 
     
     
         41 . The apparatus of  claim 40  wherein the hub proximal end borders the openings. 
     
     
         42 . The apparatus of  claim 35  wherein the hub distal end borders the openings. 
     
     
         43 . The apparatus of  claim 42  wherein the hub proximal end borders the openings. 
     
     
         44 . The apparatus of  claim 35  wherein the drive shalt is configured to drive the broaching members in rotation. 
     
     
         45 . The apparatus of  claim 35  wherein the broaching members are sufficiently resilient to be contracted into a sheath; and
 in operation, when the sheath is retracted, the broaching members are configured to expand away from the drive shaft. 
 
     
     
         46 . The apparatus of  claim 35  wherein the broaching members are biased away from the longitudinal direction. 
     
     
         47 . The apparatus of  claim 35  wherein each face has a face first end and a face second end;
 each face first end abuts the hub distal end; and 
 each face second end abuts the hub proximal end. 
 
     
     
         48 . The apparatus of  claim 35  wherein each face has a length along the longitudinal direction and the length is greater than a diameter of the distal end of each broaching member. 
     
     
         49 . The apparatus of  claim 35  wherein, in operation, the proximal end of each broaching member is angled at an angle that extends away from the radial direction. 
     
     
         50 . The apparatus of  claim 35  wherein, in operation, the distal end of each broaching member extends in the radial direction through one of the openings. 
     
     
         51 . The apparatus of  claim 35  herein the hub includes broaching edges. 
     
     
         52 . Apparatus for preparing a bone cavity for implantation of implant, the apparatus comprising:
 a drive shaft defining a radial direction and a longitudinal direction;   a hub fixed to a terminal end of the drive shaft, the hub including a hub distal end and a plurality of faces extending away from the hub distal end toward a hub proximal end, the faces spaced circumferentially apart from each other about the longitudinal direction to define openings therebetween;   a plurality of bone broaching members; and   a plurality of supporting members, each supporting member supporting one of the bone broaching members and having a proximal end and a distal end, wherein each proximal end is coupled to one of the hone broaching members;   wherein:
 the hub supports each supporting member; 
 in operation, a distal end of each supporting member extends in the radial direction; and 
 each face follows a constant radius along the longitudinal direction. 
   
     
     
         53 . The apparatus of  claim 52  wherein each bone broaching member includes a cutting edge. 
     
     
         54 . The apparatus of  claim 52  wherein the drive shaft is configured to drive the bone broaching members and the supporting members in rotation. 
     
     
         55 . The apparatus of  claim 52  further comprising, when the proximal end is a supporting member proximal end and the distal end is a supporting member distal end, a proximal hub fixed, proximal to the distal hub, to the drive shaft wherein:
 each bone broaching member includes a bone broaching member distal end and a bone broaching member proximal end; 
 each bone broaching member distal end is coupled to one of the supporting member proximal ends; and 
 each bone broaching member proximal end is supported by the proximal hub. 
 
     
     
         56 . The apparatus of  claim 52  wherein the supporting members are formed from a metal tube that is cut into a pattern. 
     
     
         57 . The apparatus of  claim 52  wherein the hub is constructed of laser-cut tube. 
     
     
         58 . The apparatus of  claim 52  wherein the hub distal end includes a flat, disc-shaped cap that borders the openings. 
     
     
         59 . Apparatus for preparing a bone cavity for implantation of an implant, the apparatus comprising:
 a drive shaft defining a radial direction and a longitudinal direction;   a broaching member having a proximal end and a distal end; and   a hub fixed to a terminal end of the drive shaft, the hub including a hub distal end, a first face and a second face, the first and second faces extending away from the hub distal end toward a hub proximal end, the first and second faces being spaced circumferentially apart from each other about the longitudinal direction to define an opening therebetween;   wherein
 the hub supports the broaching member; 
 in operation, a distal end of the broaching member extends in the radial direction; and 
 the first and second faces follow a constant radius along the longitudinal direction. 
   
     
     
         60 . The apparatus of  claim 59  further comprising, when the hub is a distal hub, a proximal hub fixed, proximal to the distal hub, to the drive shaft, wherein the proximal end of the broaching member is supported by the proximal hub. 
     
     
         61 . Apparatus for preparing a bone cavity for implantation of an implant, the apparatus comprising:
 a drive shaft defining a radial direction and a longitudinal direction;   a hub fixed to a terminal end of the drive shaft, the hub including a hub distal end, a first face and a second face, the first and second faces extending may from the hub distal end toward a hub proximal end, the first and second faces being spaced circumferentially apart from each other about the longitudinal direction define an opening therebetween;   a bone broaching member; and   a supporting member, the supporting member supporting the bone broaching member and having a proximal end and a distal end, wherein the proximal end is coupled to the bone broaching member;   wherein:
 the hub supports the supporting member; 
 in operation, the distal end of the supporting member extends in the radial direction; and 
 each face follows a constant radius along the longitudinal direction. 
   
     
     
         62 . The apparatus of  claim 61  further comprising, when the hub is a distal hub, a proximal hub fixed, proximal to the distal hub, to the drive shaft, the hone broaching member being coupled to the proximal hub.